1. Field of the Invention
The object of the present invention is an apparatus and method for network initiated redial. The method finds its application in communication systems such as telephones, videoconferencing systems or the like wherein two users/mobile devices establish a communication channel between each other.
2. Description of the Related Art
The present invention concerns improving the ease of use with respect to redial operations when two persons/mobile devices are trying to connect to each other at the same or substantially the same time.
Such substantially simultaneous connection situation frequently occurs when, for example at least one mobile device looses access to the network, a client mobile device freezes and needs a reboot, a network error occurs during connection, a low battery condition occurs or similar, followed by an immediate simultaneous redial of both persons or mobile devices.
Another possible cause of a simultaneous dialing may occur when one person tries to call another who does not pick up the call. The caller retries while the recipient having noticed an unanswered call tries to call back simultaneously with the first person's redial.
Yet another plausible cause of a simultaneous dialing may occur when two persons or mobile devices try to call each other accidentally at the same time, for example at a set time of a meeting or at a time of frequent calls such as new year's eve.
Prior art patent publication U.S. Pat. No. 7,319,861 B2 entitled “Network initiated auto-redial” discloses network initiated auto redialing, which is based on an auto redial duration selected or entered by a calling party. An auto redial interval or retry rate may also be selected or entered by the calling party. If the calling party is unavailable when a connection is established with a called party, a message is played or sent to the called party explaining that the call is an auto redial call. The message may explain that the calling party is now unavailable. Additionally, the message may include identifying information regarding the calling party. For example, the message may include a directory number of the calling party.
This publication concerns a typical callback when busy. If a user has such service enabled and receives a busy signal, the network will try to redial the other party for a predefined period of time. Therefore it would not apply to a situation of substantially simultaneous dialing by both parties.
Typically such redial approach will takes longer to succeed because it does not take into account the state of the other party when attempting a redial operation.
U.S. Pat. No. 6,169,786 B1 discloses a method for redialing in telecommunication networks for a callback when the line is not busy. If a caller attempts a call to reach a called subscriber, but the subscriber initially does not answer the call, then a redial function is automatically performed by the telecommunication network in predetermined time intervals within a predetermined time window.
Another prior art patent publication U.S. Pat. No. 7,469,044 B2 entitled “Callback when not engaged by means of automated redialing in communication network” discloses a method of redialing in telecommunication networks for a call back when not engaged, whereby a caller carries out a call attempt to reach a callee, whereby the callee does not respond at first. According to the presented apparatus and method, the callee may be reached without the caller having to continually undertake a further call attempt, whereby a radialling is automatically carried out by the relevant exchange within a given time window at given time periods and a connection to the callee is established should the same respond.
This method concerns performing a redial for a callback when not busy in telecommunications networks, which operate independently of the used telecommunication network and the telecommunication mobile device. This, however does not address a situation when both users or mobile devices are engaged with dialing each other simultaneously or substantially simultaneously and none of them may succeed.
Taking into account the foregoing prior art, there is a need to design and implement an improved apparatus and method for network initiated redial especially applicable to situations of simultaneous or substantially simultaneous dialing by both parties/mobile devices.